A.l will make leao. --> I will play with Lego.

=> Corrected: The sentence is corrected grammatically.​

B.I'm going.  Wait please.  --> I'm coming, wait a minute.

=> Your sentence has a correct grammatical structure, but this has the correct usage/expression.​

  Ouch! Very bad day.  --> Ouch! It's a bad day.

=> Corrected: The sentence is corrected grammatically.​

 Look out! Simsoon. --> Watch out, Simsoon!

=> Your sentence has a correct grammatical structure, but this has the correct usage/expression.​​